From mboxrd@z Thu Jan 1 00:00:00 1970 X-Spam-Checker-Version: SpamAssassin 3.4.4 (2020-01-24) on polar.synack.me X-Spam-Level: X-Spam-Status: No, score=-1.9 required=5.0 tests=BAYES_00 autolearn=unavailable autolearn_force=no version=3.4.4 Path: eternal-september.org!reader01.eternal-september.org!reader02.eternal-september.org!news.eternal-september.org!news.eternal-september.org!feeder.eternal-september.org!news.glorb.com!peer02.iad!feed-me.highwinds-media.com!news.highwinds-media.com!border1.nntp.dca1.giganews.com!nntp.giganews.com!buffer1.nntp.dca1.giganews.com!buffer2.nntp.dca1.giganews.com!nntp.earthlink.com!news.earthlink.com.POSTED!not-for-mail NNTP-Posting-Date: Wed, 07 Dec 2016 07:10:59 -0600 From: Dennis Lee Bieber Newsgroups: comp.lang.ada Subject: Re: Ada 2012 Constraints (WRT an Ada IR) Date: Wed, 07 Dec 2016 08:10:59 -0500 Organization: IISS Elusive Unicorn Message-ID: References: <47366b42-c0a3-41bf-a44a-5241c109d60f@googlegroups.com> <58f477d2-8b01-4001-bad8-47ea73424f4c@googlegroups.com> <6e206c3b-d4a8-44ab-9e0e-adb0924983ef@googlegroups.com> <10e8cb52-1cbd-40ed-ba11-f474c2263ced@googlegroups.com> <84oe4cdv010g9fba0jrjv2os7c0halucd0@4ax.com> X-Newsreader: Forte Agent 6.00/32.1186 X-No-Archive: YES MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit X-Usenet-Provider: http://www.giganews.com NNTP-Posting-Host: 108.68.179.180 X-Trace: sv3-F8BSwY5Fs2TjT8b6vMEUw4iF1YxSXI2BjdhPiuV0FBoE6TYdYq0fPzlUW5xawGcFdfNqa2bjm8ZRcQt!Gb3sibrp0lv6kMDIEXsjZYfQaA4Lpl22UPSmuAhOfTL84ZUPQyzkw9Q01+rsQIhrlh+lO6kobz1h!6aLhL0qHvXHmOe428KwEai3adpTi X-Abuse-and-DMCA-Info: Please be sure to forward a copy of ALL headers X-Abuse-and-DMCA-Info: Otherwise we will be unable to process your complaint properly X-Postfilter: 1.3.40 X-Original-Bytes: 2615 X-Received-Bytes: 2737 X-Received-Body-CRC: 2340031131 Xref: news.eternal-september.org comp.lang.ada:32653 Date: 2016-12-07T08:10:59-05:00 List-Id: On Wed, 7 Dec 2016 08:36:18 +0200, Niklas Holsti declaimed the following: >I don't know enough about the iAPX432 to compare the protection levels, >but it seems that the Mill will catch a lot of the common protection >violations and other undefined behaviour in C programs. > I'd have to dig up the hard-cover book I'd bought in the 80s covering the iAPX432. For the time period, the processor had to be split into two separate chips -- something like one to do the security checks before passing the fetched data/code to the execution unit; couldn't fit it all into one piece of silicon. According to Wikipedia, it also relied upon the segment/offset type of access -- with a segment table holding the access rights for the object... Even code fetches were checked for access rights. Oh -- and the offset into a segment? That was a /bit/ offset, not byte oriented -- meaning a segment could be at most 8kBytes. -- Wulfraed Dennis Lee Bieber AF6VN wlfraed@ix.netcom.com HTTP://wlfraed.home.netcom.com/